CNBC | Oil spikes 7% above $31 as cold snap boosts demand CNBC Oil prices rose as much as 7 percent on Friday to above $31 in their largest weekly rally in three months, as a cold front sweeping the United States and Europe as well as firmer financial markets gave traders reason to cash in on record short positions. Oil Prices Rally Above $31 a Barrel on Central Bank Stimulus Hopes Why Iran Doesn't Care About the Price of Oil Oil prices jump on stimulus hopes despite glut |